THF (tetrahydrofuran) resin reactor feed preheating system

Abstract

The utility model belongs to the field of PTMEG (polytetramethylene ether glycol) devices, and particularly relates to a THF (tetrahydrofuran) resin reactor feed preheating system which comprises a reactor and a preheating heat exchanger, the reactor is connected with a steam pipeline for supplying heat to the reactor, a feed port of the reactor is connected with a feed pipeline, the feed pipeline is provided with the preheating heat exchanger for preheating the feed of the reactor, and the preheating heat exchanger is connected with the reactor. The steam pipeline is connected to the preheating heat exchanger through a preheating pipeline to supply heat; the top of the reactor is connected with a gas phase outlet pipeline; and the gas phase outlet pipeline is connected with a nitrogen pipeline. The BDO is heated by the heat exchanger before entering the reactor, and enters the reactor for reaction after being slowly heated to the reaction temperature, so that the problems that the service life of the catalyst is shortened and excessive tar and other byproducts are generated due to the fact that the BDO enters the tube nest of the reactor, heat exchange is not uniform, and the catalyst is damaged and excessive side reactions are generated due to overhigh steam temperature are avoided; the reaction quality is effectively improved while the reaction stability is ensured.

Description

Technical Field

[0001] The utility model belongs to the field of PTMEG devices, and in particular relates to a THF resin reactor feed preheating system. Background Art

[0002] The cyclization process of the PTMEG unit is a process that uses BDO as raw material and resin as catalyst to catalyze the reaction to produce THF. The reactor is a fixed bed multi-tubular reactor with resin catalyst installed in the tubes. The shell side of the reactor is heated by low-pressure steam. THF and water are generated under the catalytic action of the resin and removed from the top of the reactor. In the existing process configuration, BDO enters the reactor and is then heated, which will lead to uneven heat exchange after the reactor tubes, excessive steam temperature will damage the catalyst and produce too many side reactions, resulting in a reduced catalyst life and excessive production of by-products such as tar. Summary of the invention

[0003] In view of the defects of the above-mentioned prior art, the purpose of the utility model is to provide a THF resin reactor feed preheating system, which is technically improved on the basis of the existing THF resin reactor, and a heat exchanger is set to heat BDO before entering the reactor, and then BDO is slowly heated to the reaction temperature and enters the reactor for reaction.

[0004] To achieve the above-mentioned purpose, the technical solution of the utility model is as follows: a THF resin reactor feed preheating system, comprising a reactor and a preheating heat exchanger, the reactor is connected to a steam pipeline for supplying heat to it, the feed port of the reactor is connected to a feed pipeline, the feed pipeline is provided with a preheating heat exchanger for preheating the reactor feed, the steam pipeline is connected to the preheating heat exchanger through the preheating pipeline for heating; the top of the reactor is connected to a gas phase outlet pipeline, and the gas phase outlet pipeline is connected to a nitrogen pipeline.

[0005] Furthermore, the liquid phase outlet of the reactor is connected to a liquid phase discharge pipeline, and a circulation pump is provided on the liquid phase discharge pipeline.

[0006] Furthermore, a first jumper is arranged between the feed pipeline and the liquid phase discharge pipeline, one end of the first jumper is connected to the outlet pipe section of the preheating heat exchanger, and the other end of the first jumper is connected to the inlet pipe section of the circulation pump, and a first jumper valve is arranged on the first jumper.

[0007] Furthermore, a second cross-line and a third cross-line are arranged between the feed pipeline and the liquid phase discharge pipeline, one end of the second cross-line is connected to the outlet pipe section of the preheating heat exchanger, the other end of the second cross-line is connected to the outlet pipe section of the circulating pump, and a second cross-line valve is arranged on the second cross-line; one end of the third cross-line is connected to the outlet pipe section of the preheating heat exchanger, the other end of the third cross-line is connected to the outlet pipe section of the circulating pump, and a third cross-line valve is arranged on the third cross-line.

[0008] Furthermore, the reactor is connected with a first steam condensate outlet pipeline.

[0009] Furthermore, the preheating heat exchanger is connected to a second steam condensate outlet pipeline, and the condensate after heat exchange in the preheating pipeline is discharged from the preheating heat exchanger through the second steam condensate outlet pipeline.

[0010] Furthermore, valves are provided on the preheating pipeline and the feed pipeline connecting the preheating heat exchanger at the inlet and outlet of the preheating heat exchanger.

[0011] Furthermore, the reactor feed is heated from 50°C to 100-130°C after heat exchange in a preheating heat exchanger.

[0012] The beneficial effects of the utility model are as follows: the feed preheating system sets a heat exchanger to heat the BDO before it enters the reactor, and slowly heats it to the reaction temperature before entering the reactor for reaction, thereby replacing the original design of heating the BDO after it enters the reactor, thereby avoiding uneven heat exchange after the BDO enters the reactor tubes, damage to the catalyst caused by excessive steam temperature, and excessive side reactions, resulting in reduced catalyst service life and excessive production of by-products such as tar, thereby ensuring the stability of the reaction while effectively improving the reaction quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a process flow chart of the feed preheating system of the THF resin reactor of the utility model;

[0014] In the figure: 1, reactor, 2, preheating heat exchanger, 3, steam pipeline, 4, feed pipeline, 5, preheating pipeline, 6, first steam condensate outlet pipeline, 7, second steam condensate outlet pipeline, 8, gas phase outlet pipeline, 9, nitrogen pipeline, 10, liquid phase discharge pipeline, 11, circulation pump, 12, first cross-line, 13, second cross-line, 14, third cross-line, 15, first cross-line valve, 16, second cross-line valve, 17, third cross-line valve, 18, liquid phase discharge valve. DETAILED DESCRIPTION

[0015] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0016] See attached Figure 1 A THF resin reactor feed preheating system comprises a reactor 1 and a preheating heat exchanger 2. The shell of the reactor 1 is connected with a steam pipeline 3 for supplying heat thereto, and the steam pipeline 3 contains low-pressure steam. The reactor 1 is connected with a first steam condensate outlet pipeline 6, and the condensate in the shell of the reactor 1 is discharged through the first steam condensate outlet pipeline 6; the feed port of the reactor 1 is connected with a feed pipeline 4, and the feed pipeline 4 is provided with a preheating heat exchanger 2 for preheating the feed of the reactor 1; the steam pipeline 3 is preheated by The pipeline 5 is connected to the preheating heat exchanger 2 for heat supply, and the BDO raw material at 50°C is slowly heated to the reaction temperature (100-130°C) and then enters the reactor 1 for reaction. The preheating heat exchanger 2 is connected to the second steam condensate outlet pipeline 7, and the condensate formed after the low-pressure steam in the preheating pipeline 5 is heat-exchanged is discharged from the preheating heat exchanger 2 through the second steam condensate outlet pipeline 7; the top of the reactor 1 is connected to the gas phase outlet pipeline 8, and the gas phase outlet pipeline 8 is connected to the nitrogen pipeline 9, and the pressure of the gas phase outlet pipeline 8 is adjusted by the nitrogen pipeline 9.

[0017] Furthermore, the liquid phase outlet of the reactor 1 is connected to a liquid phase discharge pipeline 10 , and the liquid phase discharge pipeline 10 is provided with a circulation pump 11 and a liquid phase discharge valve 18 .

[0018] Furthermore, a first cross-line 12, a second cross-line 13 and a third cross-line 14 are arranged between the feed pipeline 4 and the liquid phase discharge pipeline 10, one end of the first cross-line 12 is connected to the outlet pipe section of the preheating heat exchanger 2, the other end of the first cross-line 12 is connected to the inlet pipe section of the circulating pump 11, and a first cross-line valve 15 is arranged on the first cross-line 12; one end of the second cross-line 13 is connected to the outlet pipe section of the preheating heat exchanger 2, the other end of the second cross-line 13 is connected to the outlet pipe section of the circulating pump 11, and a second cross-line valve 16 is arranged on the second cross-line 13; one end of the third cross-line 14 is connected to the outlet pipe section of the preheating heat exchanger 2, the other end of the third cross-line 14 is connected to the outlet pipe section of the circulating pump 11, and a third cross-line valve 17 is arranged on the third cross-line 14.

[0019] Furthermore, valves are provided at the inlet and outlet of the preheating heat exchanger 2 on the preheating pipeline 5 and the feed pipeline 4 connecting the preheating heat exchanger 2, and the valves are used to control the on-off of the pipeline and cut off the preheating heat exchanger for maintenance.

[0020] The utility model changes the original process of BDO at 50°C entering the reactor and then being heated by shell-side steam for reaction to BDO entering the reactor for reaction after being heated to the reaction temperature by the preheater E01. Based on the existing THF resin reactor R01, a technical transformation is carried out, and a heat exchanger E01 is set before BDO enters the reactor R01 for heating, and BDO enters the reactor for reaction after slowly heating to the reaction temperature (100-130°C), replacing the original design of BDO entering the reactor R01 at 50°C and then being heated, avoiding uneven heat exchange after BDO enters the reactor tubes, damage to the catalyst caused by excessive steam temperature, and excessive side reactions, resulting in reduced catalyst service life and excessive tar and other by-products.

[0021] It should be noted that the parts not described in detail in the present invention are prior art.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] The above examples are only the best embodiments of the present invention. Obviously, the present invention is not limited to the above examples, and there are many variations. All variations that can be directly derived or associated with the contents disclosed by a person skilled in the art should be considered as the protection scope of the present invention.

Claims

1. A THF resin reactor feed preheating system, characterized in that: The invention comprises a reactor and a preheating heat exchanger, wherein the reactor is connected to a steam pipeline for supplying heat thereto, a feed pipeline is connected to the feed port of the reactor, a preheating heat exchanger for preheating the feed to the reactor is arranged on the feed pipeline, the steam pipeline is connected to the preheating heat exchanger through the preheating pipeline for supplying heat; the top of the reactor is connected to a gas phase outlet pipeline, and the gas phase outlet pipeline is connected to a nitrogen pipeline.

2. A THF resin reactor feed preheating system according to claim 1, characterized in that: The liquid phase outlet of the reactor is connected to a liquid phase discharge pipeline, and a circulation pump is arranged on the liquid phase discharge pipeline.

3. A THF resin reactor feed preheating system according to claim 2, characterized in that: A first cross-line is arranged between the feed pipeline and the liquid phase discharge pipeline, one end of the first cross-line is connected to the outlet pipe section of the preheating heat exchanger, and the other end of the first cross-line is connected to the inlet pipe section of the circulation pump, and a first cross-line valve is arranged on the first cross-line.

4. A THF resin reactor feed preheating system according to claim 2, characterized in that: A second cross-line and a third cross-line are arranged between the feed pipeline and the liquid phase discharge pipeline, one end of the second cross-line is connected to the outlet pipe section of the preheating heat exchanger, the other end of the second cross-line is connected to the outlet pipe section of the circulation pump, and a second cross-line valve is arranged on the second cross-line; one end of the third cross-line is connected to the outlet pipe section of the preheating heat exchanger, the other end of the third cross-line is connected to the outlet pipe section of the circulation pump, and a third cross-line valve is arranged on the third cross-line.

5. A THF resin reactor feed preheating system according to claim 1, characterized in that: The reactor is connected with a first steam condensate outlet pipeline.

6. A THF resin reactor feed preheating system according to claim 1, characterized in that: The preheating heat exchanger is connected to a second steam condensate outlet pipeline, and the condensate after heat exchange in the preheating pipeline is discharged from the preheating heat exchanger through the second steam condensate outlet pipeline.

7. A THF resin reactor feed preheating system according to claim 1, characterized in that: Valves are arranged on the preheating pipeline and the feed pipeline connecting the preheating heat exchanger at the inlet and outlet of the preheating heat exchanger.

8. A THF resin reactor feed preheating system according to claim 1, characterized in that: The reactor feed is heated from 50°C to 100-130°C after heat exchange in a preheating heat exchanger.

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